In Pictures: Oklahoma City bombing memorial

The view from the 9:01 gate to the 9:03 gate, conceptually framing the Oklahoma City Memorial site at 9:02, the time on April 19, 1995, when a massive fertiliser bomb planted in a rental truck ripped through the Alfred P Murrah Federal Building.

Until Barack Obama visited the Keystone Pipeline on March 22, 2012, and stayed over in the capital, no sitting US president had spent the night in Oklahoma since 1992 - before the Oklahoma City attack that killed 168 people and wounded 700 others.

The bomb blast, considered an act of domestic terrorism, was the worst single instance of any type of terrorism in the US until the September 11, 2001, attacks.

The dead mostly included employees of the federal government who had just arrived in their offices for the start of the work day, as well as 19 children who were at a day-care centre on the building's second floor. The widespread destruction masterminded by Timothy McVeigh and Terry Nicholes, in addition to the response by emergency teams across the region and beyond, became the main event in America's national consciousness associated with Oklahoma City.

The site's outdoor memorial was dedicated by President Bill Clinton in 2000, and then President George W Bush attended the museum dedication in 2001. Expansion of the current building has entered the planning stages, in advance of 20th anniversary ceremonies for 2015.

Al Jazeera spoke with some visitors about the memorial's symbolism, recollections from 17 years ago and the 2012 presidential election.

Several locals pause at the reflecting pool, which stands where Fifth Street formerly crossed in front of the building. The grass-covered area to the south is where the actual building stood.

Chuck Yeager, a Vietnam War veteran visiting from Virginia, told Al Jazeera: "We should honour everyone that(***)s sacrificed. This is what [we] have all fought for." He continued, "I don(***)t really get into the politics, but [the attack here] was contrary to the beliefs of the American public."

Jose Joglar, left, a logistics co-ordinator at an oil company in Houston, and his son Dereck, a high school student enrolled as a cadet in the Marines ROTC, visited for their first time. The father said of the Oklahoma City attack: "They tried to hit us as hard as they could, but we got up again."

"We are vulnerable," Joglar said, leaning over to touch the memorial stone for one of the victims. "And it doesn(***)t have to be someone from the Middle East. There could be something right now, and boom, we(***)re dead." He then added that he plans to vote Republican in 2016, after voting for Obama in 2012 to stabilise the economy.

Each chair, lined up in the "Field of Empty Chairs" according to the floors on which people died, represents one victim. Three people on active military duty perished in the attack, including an air force soldier on the first floor, and two members of the Marines on the sixth floor - one of whose wreathes is pictured.

Tiles created by schoolchildren across the US aimed to console local children with messages like "Healing the Heartland".

Inside the museum, a list of the federal agencies which were housed in the former Murrah building include the US Postal Service, Bureau of Alcohol, Tobacco and Firearms and the Secret Service.

The Oklahoma City National Memorial & Museum holds a clock that stopped at the time of the blast and a broken pencil sharpener.

Photographs of the deceased victims are on display to visitors, in addition to exhibitions about rescue efforts, police investigation and survivor experiences.

Lola Davenport, left, Lisa Flores and Liza Charay say they will support Obama in the coming election. Davenport recalls being at her government office in Topeka, Kansas, when the bombing took place. "All the calculators stopped," she recalled. Charay, who was 14 at the time, said, "It makes me sad how easily people forget."

A group of Oklahoma residents gathers next to the "Survivor Tree", a century-old American Elm with a message that reads: "The spirit of this city and this nation will not be defeated; our deeply rooted faith sustains us."

Tom and Debbie Steinmetz, from Bonner Springs, Kansas, recall being on a tour of the White House in Washington DC on the day of the Oklahoma City attacks, and then on a tour of the FBI headquarters on the day that the primary suspect was confirmed to have been arrested. "All the agents were high-fiving each other," Debbie said.

The Steinmetz(***)s daughter has served time treating the wounded at US military hospitals in both Iraq and at Camp Bastion in Afghanistan. The "independent" couple did not state their voting preference for the presidential election but implied it was not the incumbent.

The couple, who had purchased political "soda pop" nearby, described themselves as fiscally conservative and socially moderate, saying they would vote in November for the "best" candidate. Tom said he was "born and raised a Catholic Democrat" but that he resents the "culture of dependency on government".